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Improvement of water resistance of long afterglow SrAl_2O_4: Dy, Eu phosphor by coating with SiO_2 film

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Rare Metals 2002年第2期21卷 152-155页

作者： ZHANG junying, chen Qingming, LIN Yuanhua, and ZHANG ZhongtaiState Key Laboratory of New Ceramics and Fine Processing, Department of Materials Science and Engineering, Tsinghua University,Beijing 100084, China Department of Materials Science and Engineering Tsinghua University State Key Laboratory of New Ceramics and Fine Processing 北京 100084

The long afterglow SrAl_2O_4: Dy, Eu phosphor is liable tohydrolyze in water with deterioration of the lumin- escent ***_2O_4: Dy, Eu phosphors were therefore heated at 60-90 deg. C inTEOS sol to form a surface gel and then heat-treated at 400 deg. C toobtain SiO_2 coated phosphors. Observation by ?Transmission ElectronMicroscope (TE) and X- ray photoelectron spectroscopy (XPS) showsthat a thin silica film forms on the surface of the phosphors. Thecoating procedure can be illustrated by a four-step process and thetransparent silica film can suppress the hydrolysis process, so thatthe luminescent properties of the phosphors are unimpaired or evenbetter.

关键词： phosphors coating luminescent materials SrAl_2O_4

Analysis of the merged quasi-geoid of neighbouring areas

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Geodesy and Geodynamics 2018年第4期9卷 296-301页

作者： Chunxi Guo Jianliang Nie Bin Wang Jie Tian Guangwei Jiang junying chen Shijuan Zhang Geodetic Data Processing Centre National Administration of Surveying Mapping and Geoinformation of China

Employing the merged quasi-geoid, we analyses the causes of systematic errors in modelling of quasigeoid of neighbouring areas in the paper, and the efficient method is introduced to improve the accuracy of quasi-geoid. First, the systematic error is weakened with the moving window method applied to established quasi-geoids in two adjacent regions, and the accuracy of the merged quasi-geoid in the stitching region is checked using the measured GPS benchmark data; Second, the whole quasi-geoid is recomputed with data obtained from two adjacent regions if the accuracy of the quasi-geoid obtained from the first step in the stitching region is low; Finally, the quasi-geoids in two adjacent regions are recomputed respectively using GPS benchmark data of own region and adjacent region with the same solution if the accuracy of whole quasi-geoid obtained from the second step also is low. Actual data sets from Sichuan Province and Chongqing City are employed to test the moving window method. It is shown that the quasi-geoid models with high resolution and accuracy were obtained.

关键词： Merged quasi-geoid Moving window Systematic error

InGaAs/GaAs/InGaP Strained Quantum Well Lasers Grown by Metalorganic Chemical Vapor Deposition

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Journal of Semiconductors 1998年第7期 69-72页

作者： Yang Guowen Xu Zuntu Ma Xiaoyu Xu junying Zhang Jingming chen Lianghui (Institute of Semiconductors, The Chinese Academy of Sciences, Beijing 100083)

１ＩｎｔｒｏｄｕｃｔｉｏｎＳｔｒａｉｎｅｄＩｎＧａＡｓ／ＧａＡｓｑｕａｎｔｕｍｗｅｌ（ＱＷ）ｌａｓｅｒｓｗｉｔｈｅｍｉｓｉｏｎｗａｖｅｌｅｎｇｔｈｏｆ９８０ｎｍａｒｅｃｕｒｅｎｔｌｙｒｅｃｅｉｖｉｎｇｃｏｎｓｉｄｅｒ... 详细信息

１ＩｎｔｒｏｄｕｃｔｉｏｎＳｔｒａｉｎｅｄＩｎＧａＡｓ／ＧａＡｓｑｕａｎｔｕｍｗｅｌ（ＱＷ）ｌａｓｅｒｓｗｉｔｈｅｍｉｓｉｏｎｗａｖｅｌｅｎｇｔｈｏｆ９８０ｎｍａｒｅｃｕｒｅｎｔｌｙｒｅｃｅｉｖｉｎｇｃｏｎｓｉｄｅｒａｂｌｅａｔｅｎｔｉｏｎｂｅｃａｕ...

关键词： InGaAs/GaAs/InGaP Strained Quantum Well Metalorganic Chemical Deposition

Copper‐doped zinc sulfide nanoframes with three‐dimensional photocatalytic surfaces for enhanced solar driven H_(2) production

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Chinese Journal of Catalysis 2022年第3期43卷 782-792页

作者： Junmin Huang Jianmin chen Wangxi Liu Jingwen Zhang junying chen Yingwei Li State Key Laboratory of Pulp and Paper Engineering School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510640GuangdongChina

Solar‐to‐chemical energy conversion is perceived as one of the most potential solutions to the current energy and environmental crisis,yet requires major scientific endeavors on the development of efficient and sustainable *** the composition and morphology of a semiconductor jointly for the purpose of improving photocatalysis efficiency remains ***,we rationally fabricated Cu‐doped ZnS nanoframes via a simple conjunct strategy of substitutional doping,chemical acidic etching,and sulfidation,aiming at enhancing the light utilization and charge separation/transfer efficiency for solar‐light‐driven hydrogen ***‐doped zeolitic imidazolate framework‐8(ZIF‐8)rhombic dodecahedrons are transformed to hollow Cu‐ZIF‐8 nanoframes converted to Cu‐ZnS nanoframes with three‐dimensional photocatalytic active surfaces via anisotropic chemical etching,which is further converted to Cu‐ZnS *** combining the merits of optimal heteroatom doping and frame‐like open architecture,the obtained 1%Cu‐doped ZnS nanoframe exhibits high photocatalytic activity under solar light irradiation with improved hydrogen production rate up to 8.30 mmol h^(–1) g^(–1) and excellent stability in the absence of cocatalysts,which is significantly improved in comparison with those of the bare ZnS and Cu‐ZnS with different *** work inspired by merging the merits of metal doping and anisotropic chemical etching may shed light on the rational design and fabrication of advanced photocatalysts.

关键词： Metal‐organic frameworks Solar‐to‐chemical energy conversion Metal sulfides Hydrogen production Photocatalysis

Metal–organic-framework-based catalysts for hydrogenation reactions

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Chinese Journal of Catalysis 2017年第7期38卷 1108-1126页

作者：陈芝杰陈俊英李映伟华南理工大学化学与化工学院广东省燃料电池技术重点实验室广东广州510640

Metal-organic-framework （MOF）-based materials with novel physicochemical properties have emerged as promising catalysts for various hydrogenation reactions. In addition to metal clusters and multifunctional organic ligands, MOF-based catalysts can incorporate other functional species, and thus provide various active sites for hydrogenation processes. The structural properties of the catalysts play significant roles in enhancing the interactions among the reactants, products, and catalytic sites, which can be rationally designed. Because of the synergistic effects between the ac-tive sites and the structural properties, MOF-based catalysts can achieve higher activities and selec- tivities in hydrogenation reactions than can be obtained using traditional heterogeneous catalysts. This review provides an overview of recent developments in MOF-based catalysts in the hydro-genation of alkenes, alkynes, nitroarenes, cinnamaldehyde, furfural, benzene, and other compounds. Strategies for improving the catalytic performances of MOF-based catalysts are discussed as well as the different active sites and structural properties of the catalysts.

关键词： Metal-organic framework Hydrogenation Heterogeneous catalysis Nanoparticle Chemoselectivity Synergistic effect

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坡地喷灌水滴直径与动能强度分布规律研究

农业机械学报 2018年第6期49卷 263-270页

作者：张林惠鑫陈俊英西北农林科技大学水土保持研究所陕西杨凌712100 西北农林科技大学水利与建筑工程学院陕西杨凌712100

在室内无风条件下应用视频雨滴谱仪实时监测了不同坡度下喷洒水滴直径和速度等信息,研究了不同坡度下水滴平均直径及直径频率沿射程方向的变化规律,分别建立了水滴平均直径、速度与坡度等之间的数学关系。以此为基础,结合坡地喷灌水量... 详细信息

在室内无风条件下应用视频雨滴谱仪实时监测了不同坡度下喷洒水滴直径和速度等信息,研究了不同坡度下水滴平均直径及直径频率沿射程方向的变化规律,分别建立了水滴平均直径、速度与坡度等之间的数学关系。以此为基础,结合坡地喷灌水量分布计算方法,提出了无风条件下坡地喷洒水滴动能强度计算模型,并通过试验验证了该模型的正确性。以雨鸟LF1200型喷头为研究对象,应用该模型重点分析了不同喷头布置方式、间距和坡度对组合喷头打击动能强度分布的影响。结果表明:随着喷头间距的增大,动能强度分布越来越不均匀,且动能强度高值区所占比例不断减小;坡度变化对坡面动能强度分布影响并不明显;三角形布置方式对减小坡地喷灌打击动能强度具有一定作用。同时考虑打击动能强度和水量分布,在坡地喷灌系统设计时,若选用雨鸟LF1200型喷头,建议优先采用三角形布置,且间距为0.8倍的平地喷头射程。

关键词：坡地喷灌水滴直径速度动能强度

地理高考与高中地理新课程的相关分析——以2019年地理高考全国Ⅰ卷为例

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地理教学 2019年第23期 48-50页

作者：陈俊英福建教育学院

地理高考内容与高中地理新课程的内容要求关系密切,本文以2019年地理高考全国Ⅰ卷为例,着重分析了城乡空间的利用、人口增长与迁移、交通与区域的关系、产业结构的调整和旅游开发与建设等地理高考常见内容与高中地理新课程标准之间的关... 详细信息

地理高考内容与高中地理新课程的内容要求关系密切,本文以2019年地理高考全国Ⅰ卷为例,着重分析了城乡空间的利用、人口增长与迁移、交通与区域的关系、产业结构的调整和旅游开发与建设等地理高考常见内容与高中地理新课程标准之间的关联,分析了这些地理高考问题与高中地理新课程倡导的地理学科核心素养及其进阶培育的关系。地理高考命题肩负着反映国家发展战略、国际风云际会的新时代背景的重任,这样的大趋势和大方向无疑是与地理课程观念和内容的修订相一致的。地理教师要通过地理教学立德树人,就必须随时关注国家、国际时政大局,不断吸收地理学科所广泛涉及的国家大事、国际关系,方能垂范家国情怀和国际眼光的持续跟进。中学地理教师培训,尤其是高层次的国家级培训、省级骨干教师以上培训,必须大力加强地理科学与时俱进的地理教学内容培训。

关键词：地理高考地理新课程相关分析教师培训

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膜下滴灌棉田冻融期土壤剖面水盐热分布动态

排灌机械工程学报 2021年第11期39卷 1161-1168页

作者：廖海栗现文陈俊英西北农林科技大学水利与建筑工程学院陕西杨凌712100 西北农林科技大学旱区农业水土工程教育部重点实验室陕西杨凌712100

为了深入揭示干旱区膜下滴灌棉田冻融期土壤水、盐和温度的动态变化规律,利用Hydra水盐热系统实现对冻融期宽行、窄行和膜间位置15,25和40 cm深度土壤液态水分、温度和电导率实时等间隔加密监测,分析了冻融期土壤水盐热动态变化过程.结... 详细信息

为了深入揭示干旱区膜下滴灌棉田冻融期土壤水、盐和温度的动态变化规律,利用Hydra水盐热系统实现对冻融期宽行、窄行和膜间位置15,25和40 cm深度土壤液态水分、温度和电导率实时等间隔加密监测,分析了冻融期土壤水盐热动态变化过程.结果表明:同一位置不同深度液态水分、电导率和温度动态变化规律一致;冻融期内盐分垂向运移规律为深层土壤内的盐分向表层运移,冻融作用使盐分发生了重分布,加重了土壤40 cm深度的盐分含量,电导率增值范围为20~80μS/cm,并且冻融前后不同位置电导率以位置排序由大到小为宽行,窄行,膜间;在冻融过程中不同位置土壤温度、液态水分和电导率两两之间存在着正相关关系(P<0.01),其相关系数大于0.74,而电导率与温度和液态水分两者也存在极强的多元一次函数关系(P<0.01),其相关系数大于0.90;冻结和融化并不是重合的过程,而是在期间会出现分叉点,分叉点出现在-1℃附近.研究结果对制定合理的非生育期灌溉制度具有重要参考意义.

关键词：水盐运移冻融期干旱区膜下滴灌微咸水

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多聚赖氨酸修饰钛氧膜并固定纤连蛋白对内皮细胞生长的影响

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生物医学工程学杂志 2008年第4期25卷 864-869页

作者：王露陈俊英黄楠西南交通大学材料学院材料先进技术教育部重点实验室四川省人工器官表面工程重点实验室成都610031

为了进一步提高钛氧膜与内皮细胞的亲和性,研究了一种表面生物化学方法对钛氧膜表面内皮细胞生长的影响。先利用盐酸和双氧水活化钛氧膜表面,使其产生羟基基团,再涂覆多聚赖氨酸作为中间过渡层,最后在表面上固定纤连蛋白。采用傅立叶红... 详细信息

为了进一步提高钛氧膜与内皮细胞的亲和性,研究了一种表面生物化学方法对钛氧膜表面内皮细胞生长的影响。先利用盐酸和双氧水活化钛氧膜表面,使其产生羟基基团,再涂覆多聚赖氨酸作为中间过渡层,最后在表面上固定纤连蛋白。采用傅立叶红外光谱仪、X射线光电子能谱仪及接触角测量的方法对每步处理后的材料表面进行分析与测试。通过体外人脐静脉原代内皮细胞培养实验评价内皮细胞在样品表面的黏附和生长。研究结果显示,通过表面活化后涂覆多聚赖氨酸并固定纤连蛋白的方法能促进内皮细胞在钛氧膜表面的黏附和生长。

关键词：钛氧膜多聚赖氨酸纤连蛋白内皮细胞